Make the landing page translatable and add its Japanese translation#1436

Merged

eed3si9n merged 3 commits intoscala:masterfrom

exoego:ja/landing-page

Jul 19, 2019

Commits on Jul 18, 2019

Add language dropdown to masthead-documentation layout
exoego
committed
Add Japanese translations of root page (index.md)
exoego
committed
Fix missing directory separator.
exoego
committed